France announced Friday there were no survivors on board the Air Algerie flight that crashed in Mali as it emerged that several families were wiped out in the tragedy.

Such was the apparent violence of the crash -- increasingly blamed on bad weather -- that debris shown in the first available footage of the impact site were barely recognisable as parts of an aircraft.

There were conflicting tolls of whether there were 118 or 116 people aboard the flight.

"Sadly, there are no survivors," President Francois Hollande said on television, a day after the plane, carrying 54 French nationals, went down shortly after take-off from Ouagadougou in Burkina Faso.

The McDonnell Douglas 83 jet, operated by Spanish charter firm Swiftair on behalf of Air Algerie, was also carrying passengers and crew from Burkina Faso, Lebanon, Algeria, Spain, Canada, Germany and Luxembourg.

It was unclear exactly how many people were on board, as Swiftair put the number at 116 while the French presidency said 118 passengers and crew were on the jet.

On Friday, Foreign Minister Laurent Fabius revised the death toll of French nationals up from 51 to 54.

The first footage of the crash site in Mali's hard-to-reach Gossi region, filmed by soldiers from nearby Burkina Faso, showed a stark, sandy-looking terrain littered with debris, the ground blackened in some areas.

The jet was on its way to Algiers when it crashed amid reports of heavy storms in the area, shortly after the pilots radioed in that they were diverting course due to difficult weather conditions.

French Interior Minister Bernard Cazeneuve said weather conditions appeared to be the most likely cause of the accident -- the worst air tragedy for French nationals since the crash of the Air France A330 from Rio de Janeiro to Paris in June 2009.

But Hollande insisted that no potential cause for the accident was being left out.

Swiftair has a good safety record and the head of France's civil aviation authority said Thursday that the MD-83 had passed through France this week and been given the all-clear.

- Airline disaster week -

The plane crash is the third in the space of just eight days, capping a disastrous week for the aviation industry.

On July 17, a Malaysia Airlines plane crashed in eastern Ukraine, killing all 298 people on board.

And a Taiwanese aircraft crashed in torrential rain in Taiwan on Wednesday, killing 48.

France has been hugely active in search and retrieval efforts for the Air Algerie plane, dispatching military forces and crash experts to the site after one of its drones found the wreckage.

The country already has a strong military presence in the area after it launched an offensive in Mali last year to stop Islamist extremists and Tuareg rebels from marching onto Bamako.

Defence Minister Jean-Yves Le Drian told reporters that around 180 French and Malian forces had arrived on the crash site, as had 40 Dutch soldiers from the MINUSMA UN stabilisation force in Mali.

"Their mission is to make the zone secure and to allow information to be gathered, which will be essential for the investigation," he said.

The black box flight recorder of the plane has already been recovered, Hollande said earlier.

- Entire families in plane -

Whatever the cause of the crash, the human face of the tragedy was becoming ever-more poignant as the hours went by, with humanitarians, expatriates, tourists and entire families among the victims.

In one particularly tragic case, ten members of the same French family were on board the plane, the mayors of the towns where some of them lived and relatives told AFP.

The small town of Menet in central France, meanwhile, was left devastated when residents found out a family-of-four -- a couple, their ten-year-old daughter Chloe and their 14-year-old son Elno -- that lived there died.

Denise Labbe of the local town hall said Chloe had been hugely excited about the trip, but had also confided to her teacher that she was scared of taking the plane, which she was doing for the first time.

Relatives of the victims will meet Hollande and Fabius in Paris on Saturday.

Air Algerie flies the four-hour passenger route from Ouagadougou to Algiers four times a week, and the Spanish crew had already flown it five times with the same plane, Algeria's transport minister said.

This year has already seen Algeria mourn the loss of another plane when a C-130 military aircraft carrying 78 people crashed in February in the country's mountainous northeast, killing more than 70 on board.

Algerian President Abdelaziz Bouteflika announced a three-day period of national mourning starting from Friday.

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